A huge market exists for hard disk drives for mass-market computer systems such as servers, desktop computers, laptop computers, and mobile computers (e.g., PDAs and cell phones). To be competitive in this market, a hard disk drive should be relatively inexpensive, and should accordingly embody a design that is adapted for low-cost mass production. Further, there exists substantial competitive pressure to continually develop hard disk drives that have increasingly higher storage capacity, that provide for faster access to data, and at the same time conform to decreasingly smaller exterior sizes and shapes often referred to as “form factors.”
Satisfying these competing constraints of low-cost, small size, high capacity, and rapid access requires innovation in each of numerous components and methods of assembly including methods of assembly of various components into certain subassemblies. Typically, the main assemblies of a hard disk drive are a head disk assembly (“HDA”) and a printed circuit board assembly (“PCBA”).
The HDA typically includes at least one magnetic disk (“disk”), a spindle motor for rotating the disk, and a head stack assembly (“HSA”) that includes a head with at least one transducer for reading and writing data. The HSA is controllably positioned by a servo system in order to read or write information from or to particular tracks on the disk. The typical HSA has three primary portions: (1) an actuator assembly that moves in response to the servo control system; (2) a head gimbal assembly (“HGA”) that extends from the actuator assembly and biases the head toward the disk; and (3) a flex cable assembly that provides an electrical interconnect with minimal constraint on movement. The PCBA typically includes signals for processing signals and controlling operations.
Within the HDA, the spindle motor rotates the disk or disks, which are the media to and from which the data signals are transmitted via the head of the HGA. The transfer rate of the data signals is a function of rotational speed of the spindle motor, the faster the rotational speed, the higher the transfer rate.
For disk drive manufacturing, the HSA may be shipped together with a shipping comb that separates and protects the heads of the HGAs prior to the integration of the HSA into the HDA to manufacture the disk drive. In the manufacture of a disk drive with a ramp design, the HGA needs to be placed into a rested position on the ramp. The HGA may include a lift tab for resting on the ramp. This assembly may be complicated by the fact that the typical disk drive includes more than one disk and there may be multiple HGAs with read/write heads for reading from or writing to each disk surface. A typical disk drive may have an array of HGAs with read/write heads arranged in opposing pairs.
Unfortunately, loading the lift tabs of the HGAs onto the ramp during the hard disk drive assembly process may be damaging to the HGA if it is not adequately vertically aligned with the ramp. In particular, collisions may occur between the HGA and the ramp during the merge process which amounts to costly yield losses in disk drive manufacturing. Unfortunately, once the HSA is damaged, it is typically scrapped.
Accordingly, a more precise method and apparatus to merge the HGA with the ramp during the manufacturing of disk drives is sought after.